Hair transplantation procedures are well-known, and typically involve (in a patient having male pattern baldness) harvesting donor hair grafts from the side and back fringe areas (donor areas) of the patient's scalp, and implanting them in a bald area (recipient area). Historically, the harvested grafts were relatively large (3-5 mm), although more recently, the donor grafts may be single follicular units. In particular, “follicular units” are naturally occurring aggregates of 1-3 (and much less commonly, 4-5) closely spaced hair follicles that are distributed randomly over the surface of the scalp. In one well-known process, a linear portion of the scalp is removed from a donor area by dissection with a scalpel down into the fatty subcutaneous tissue. The strip is dissected (under a microscope) into the component follicular units, which are then implanted into a recipient area in respective puncture holes made by a needle. Forceps are typically used to grasp and place the follicular unit grafts into the needle puncture locations, although other instruments and methods are known for doing so.
In “Androgenetic Alopecia” (Springer 1996), M. Inaba & Y. Inaba disclose and describe a method for harvesting singular follicular units by positioning a hollow punch needle having a cutting edge and interior lumen with a diameter of 1 mm, which is about equal to the diameter of critical anatomical parts of a follicular unit. The needle punch is axially aligned with an axis of a follicular unit to be extracted and then advanced into the scalp to cut the scalp about the circumference of the selected follicular unit. Thereafter, the follicular units are easily removed, e.g., using forceps, for subsequent implantation into a recipient site with a specially devised insertion needle.
Published U.S. Patent Application 20050203545 (Cole) discloses an instrument for the extraction of individual follicular units that purportedly allows for a more precise penetration depth and angle with respect to the skin surface of the skin of a patient.
Published U.S. Patent Application 20050267506 (Harris) discloses a method and apparatus for the extraction of follicular units by first scoring the outer skin layers with a sharp punch, and then inserting a separate blunt punch into the incision to separate the hair follicular unit from the surrounding tissue and fatty layer.
U.S. Pat. No. 6,585,746 (Gildenberg) discloses a hair transplantation system utilizing a robotic system, including a robotic arm and a hair follicle introducer associated with the robotic arm. A video system is used to produce a three-dimensional virtual image of the patient's scalp, which is used to plan the scalp locations that are to receive hair grafts implanted by the follicle introducer under the control of the robotic arm. The entire disclosure of U.S. Pat. No. 6,585,746 is incorporated herein by reference.